Page:Popular Science Monthly Volume 91.djvu/882

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��Popular Science Monthly

���When liquid is heated it is changed to gas

\ Position of lever when expansion drum 13 forced down

■Shutter control rod

��The device is in two parts — an ex- pansion drum which moves a shaft and bell-crank lever to operate the shut- ters, and a syphon thermostat in the return water line to the radiator tank

��degrees Fahrenheit. The expansion of the gas creates a pressure in the tube and the flexible pipe connecting it with the expan- sion chamber, so that the latter is moved downward. This motion, by means of the system of rods and levers shown, opens the shutters slightly and admits air to the motor. This opening action has a maximum temperature point of 180 degrees with a full opening of the shutters. Should the tem- perature of the cooling water change, the shutters are opened or closed , as the case may be. to maintain an even engine temperature.

���Keeping the Engine Temperature at the Right Point Automatically

AN AUTOMOBILE manufacturer is of- , fering a model with automatically- controlled radiator shutters. His de- vice combines two well-known auto- mobile devices, the radiator shutter and the thermostatic control for the temperature of the engine water. The combination of the two de- vices has made it necessary to make the apparatus in two parts — an ex- pansion drum which moves a shaft and a bell-crank lever to operate the shutters, and a syphon thermostat in the return water line to the radiator top tank. The two parts are joined by means of a short flexible hose which ends in a small metal tube at the end of a pot in the return water line. This tube is filled with a sensi- tive liquid which changes into a gas when the temperature of the cooling water passing around the tube in the iron pot in the water line reaches 140

��How the French Prepare

Dummy Airplane Fleets for

Target Practice

WE take off our hats to the Frenchman who con- ceived the idea illustrated be- low. For simplicity of construc- tion and the efficiency with which it performs its duties, it is in a class all by itself. It is nothing more or less than a fleet of dummy airplanes sus- pended from a crossbeam at- tached to a tree to afford target practice for the French air men. The dummy planes are suspended just as any boy might suspend toy planes, except that strong wire rope is used. The rope is long enough to give plenty of opportunity for the wind to whirl and toss the planes.

���ich Official Photo

The airplane targets suspended from a crossbeam attached to a tree sway and dart about in the wind

��Maybe you have special needs. Write to the editor about anything within the scope of the magazine. He will be glad to help you.

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